[HappyHippy]

Thanks for the tip for the nipple drinkers - are they okay for really big pigs as well then?

Yes, you get really small size for piglets a bigger one for weaners and a large size for sows - they all deliver different 'flow rates'. I generally use weaner sized ones for all growing pigs and the sow size for all the adult pigs (the farrowing pen inside has a piglet size and a sow size in it at different heights) but you can get a double bracket so you could have a meduim and large size in the one paddock and you also get a height adjustable bracket (handy if you're swapping adults/weaners between pens)
If you email GE Barker they'll usually get back to you pretty quick if you need a bit of advice, or you could phone them up - they're really helpful.
Karen